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Magnetism is nothing mysterious.
Here is some of what we know:
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--- Magnetism of iron ("permanent magnetism") makes possible the magnetic compass and lets drawings be stuck to refrigerator doors. But it's just an accident of nature.
--- The true nature of the magnetic force is the attraction or repulsion between electric currents. That was discovered by Oersted and by Ampére in 1820.
--- The Earth is magnetic because electric currents flow in it (and the same with sunspots). There is no magnet inside it (it has a lot of iron, but it's too hot).
--- Electric and magnetic phenomena are closely linked. That link not only makes electric machinery possible, but also radio, microwaves, light and x-rays, all of which are "electromagnetic waves".
--- Magnetic fields have no effect on your
living tissue. Magnets don't do a thing for your health (or for your car's gas mileage).
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